CODEWITHSUNDEEP
c#.netwinformsuser-controls
Blorgbeard
Blorgbeard

Reputation: 103467

How to make a UserControl with a custom DefaultBackColor?

When I right-click on my custom UserControl's BackColor property in the property-grid, then click Reset, I would like the BackColor property to change to (for example) Color.LightGreen, and the property value to appear un-bolded, to indicate that it is the default value.

Currently, I know I can do this:

public override void ResetBackColor() {
    BackColor = Color.LightGreen;
}

Which works as far as setting it to LightGreen on reset. But it still appears bolded in the property-grid, indicating that the current value is not the default.

I notice that the Control class has a static read-only property, DefaultBackColor. Unfortunately, since it's static, I cannot override it.

Is there some way to get all the functionality I want?

Upvotes: 2

Views: 2390

Answers (2)

Devmyselz
Devmyselz

Reputation: 460

In order to make a custom control with a custom backcolor, as you itself mentioned you cannot use porperty defaultbackcolor.

Example in vb.net

   <Runtime.InteropServices.DllImport("user32.dll", ExactSpelling:=True, CharSet:=Runtime.InteropServices.CharSet.Auto)>
    Public Shared Function GetParent(ByVal hWnd As IntPtr) As IntPtr
    End Function

   Protected Overrides Sub CreateHandle()
        Dim parentHandle As IntPtr = GetParent(Me.Handle)
        ParentForm = Control.FromHandle(parentHandle)
        ParentForm.TransparencyKey = Me.BackColor
   End Sub

Upvotes: 0

Fredrik M&#246;rk
Fredrik M&#246;rk

Reputation: 158319

You can achieve this by using the DefaultValue attribute:

public UserControl1()
{
    InitializeComponent();
    this.BackColor = Color.LightGreen;
}

[DefaultValue(typeof(Color), "LightGreen")]
public override Color BackColor
{
    get
    {
        return base.BackColor;
    }
    set
    {
        base.BackColor = value;
    }
}

Upvotes: 6

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